What was the goal of the joint US-New Zealand project at the end of World War II called "Project Seal?"

"Project Seal", also know as "tsunami bomb", was an attempt during World War II to develop a tectonic weapon that could create destructive tsunamis. The project began after US Navy officer E.A. Gibson noted small waves generated by explosions used to clean coral reefs. The idea was developed by the United States and New Zealand military.

The New Zealand Army, working in close cooperation with the Air Force, Navy and the US Navy, set off a series of underwater explosions that triggered tidal waves along the coast of New Caledonia and then the Whangaparaoa Peninsula near Auckland in New Zealand between June 1944 and January 1945.

Some 3,700 bombs (mainly TNT) were detonated during the experiments, and preliminary experimental results suggested that a cascade of 10 large blasts (two thousand tons in total, 5 miles from the shore) would be sufficient to generate a 30–40 foot tsunami capable of inundating a small coastal city.

Though the testing was positive the project was shelved in early 1945. Experts concluded that single explosions were not powerful enough and a successful tsunami bomb would require about 2 million kilograms of explosive arrayed in a line about five miles from shore.

The project was directed by Professor Thomas Leech, Dean of Engineering at Auckland University, who was seconded to the military for the purpose of developing the bomb. The final report was released in 1950 and was declassified in 1999 and reported in New Zealand.